1. Field of the Invention
The invention relates to the field of tools and/or jigs as aids in locating or aligning a handrail or other stair or landing railing to its desired position, or in visualizing how such a railing might function or appear before it is installed.
2. Related Art
Handrails for stairs are normally required by relevant building codes or, at least, are very desirable. Building codes, ergonomics, and good practice require that such rails be installed parallel to the slope of the stairs and at a certain, convenient height above the stair treads. Good and expedient installation of stair rails, however, is made difficult by the nature of stairs. Stairs typically vary as to the height of the risers, the run of the treads, and, consequently, their slope. Installation is further complicated by the narrow, three-dimensional nature of stairs and stair ways and by traffic there which often must be accommodated during handrail installation. Thus, a need exists for a tool to facilitate efficient installation of stair handrails.
Wilkerson in U.S. Pat. No. 5,527,016 (issued June, 1996) discloses a"Handrail Positioning Device" for positioning a handrail above stairs during the permanent installation process. The device features adjustable-height screw jack stanchions to be screwed to the stair treads near the top and bottom of the stairs; the handrail is then clamped to adjustable arms on the stanchions. Raymond et al. in U.S. Pat. No. 3,788,608 (issued January, 1974) discloses a modular hand rail similar in some regards to Wilkerson but for temporary uses such as bleacher handrails rather than as an aid to permanent installation. The present invention, like Wilkerson, is an aid to installing handrails but functions very differently to help visualize where handrails might best be located and then to delineate the chosen location. Both Wilkerson and Raymond are classified within U.S. Class 256.
Pantographs and other aids for drawing and marking have been made which may include a parallelogram or other four sided structure. Scan in U.S. Pat. No. 4,527,341 (first issued in Sweden, October, 1983) discloses an"Angle Determination of Parallelogram Type". Nicyper in U.S. Pat. No. 4,397,090 discloses a parallelogram pantograph for graphically reproducing images. Riche in U.S. Pat. No. 669,549 discloses a pantograph for marking or cutting boot or shoe patterns.
None of the related art approaches the simplicity of the present invention and none is adapted for quick and efficient use as a handrail construction tool. Therefore, there remains a need for a handrail tool which is simple and convenient to carry and use and which assists designers, builders, and consumers alike in selecting and then implementing a handrail design.